Ian W. Webster

Physiological factors associated with falls in an elderly population

Objective: To determine whether a battery of 13 sensorimotor, vestibular, and visual tests discriminates between elderly fallers and elderly non‐fallers.

Clinical parameters associated with falls in an elderly population

Eighty-one elderly residents of a hostel for the aged (mean age 83.3 years) underwent clinical medical assessments to examine susceptibility to falling. The medical examination was structured and followed a clinical format with particular emphasis upon posture and gait, in addition to routine examination of the cardiovascular, respiratory, neurological, gastrointestinal, haemopoietic, genitourinary, musculoskeletal and visual systems. These subjects were then followed up for 1 year to assess whether these clinical measures were associated with falls. Seventy-six residents were available for follow-up. Thirty-four subjects (44.7%) reported having no falls in the follow-up year, 10 (13.2%) fell once only, 13 (17.1%) fell on two occasions whilst 19 (25.0%) fell three or more times. Seventy-two percent of all falls occurred in the hostel building. Certain clinical factors showed high specificity (i.e. only a few non-fallers screened positive in the tests) but low sensitivity (i.e. there were considerable numbers of residents who screened negatively, but fell in the 12-month follow-up period). Stepwise logistic regression analysis revealed impaired cognition, abnormal reaction to any push or pressure, history of palpitations and abnormal stepping as variables that independently and significantly predicted falling. The equation predicted falls with 70.7% sensitivity and 79.4% specificity, with an overall predictive accuracy of 74.7%. It appears that a modified focussed clinical examination could provide the basis of a short assessment for predicting falls and highlight possible intervention strategies for reducing fall risk.

Visual field dependence in elderly fallers and non-fallers

Two tests of visual field dependence (a measure of reliance upon the spatial framework provided by vision in the perception of the upright)—roll vection and the rod and frame test—were administered to 136 participants aged fifty-nine to ninety-seven years. It was found that the fifty-nine participants who had experienced one or more falls in the past year were significantly more visually field dependent in both tests compared with the seventy-seven participants who had not fallen. Mean error in perception of the true vertical in the rod and frame test was 20.7 degrees for the falters and 17.2 degrees for the non-fallers. Mean error in perception of the true vertical in the roll vection test was 6.6 degrees for the fallers and 3.6 degrees for the non-fallers. The test of roll vection was the better discriminator between fallers and non-fallers, which may be due in part to less misunderstanding of the required task by the participant. The results suggest that tilted or rolling visual stimuli may be factors leading to postural instability and falls in the elderly. The findings support the claim that greater dependence on visual information shown by fallers may be the result of reduced proprioceptive and vestibular function resulting from increased age and chronic health problems.

Socio‐economic, migrant and geographic differentials in coronary heart disease occurrence in New South Wales

Objective: This study examines the variation in coronary heart disease (CHD) mortality and acute myocardial infarction (AMI) by socio‐economic status (SES), country of birth (COB) and geography (urban/rural) in the total population of New South Wales (Australia) in 1991‐95.

One-year evaluation of three smoking cessation interventions adminidtered by general practitioners

Three smoking cessation interventions designed for use by general practitioners (GPs) within the routine consultation were evaluated in a field setting using 26 GPs throughout metropolitan Sydney. A total of 450 smoking patients were allocated to either Structured Behavioral Change with nicotine gum (Group SBCN), Structured Behavioral Change without nicotine gum (Group SBC), or GP advice with nicotine gum (Group AN). Although significant differences in the percentage of abstainers were observed between Groups SBCN and SBC three weeks after treatment (39% vs. 26%), the point prevalence abstinence rate for patients at 12 months declined to 19, 18, and 12% for Groups SBCN, SBC, and AN, respectively. Continuous abstinence to the end of the 12-month period was 9% for Groups SBCN and SBC, and 6% for Group AN. Forty-eight percent of the 450 patients made an attempt to stop smoking, and 89% reduced their cigarette consumption at some point during the study. Examination of 132 self-selecting patients who fully participated in the three interventions and attended all scheduled visits, revealed significantly larger proportions of abstainers within Groups SBCN (34%) and SBC (33%) than in Group AN (15%) at the 12-month follow-up.

The Age-Prevalence of Cardiovascular Abnormalities in Relation to the Aging of Special-Sense Function

ABSTRACT: The application of standardized multi‐test data to the study of aging is explored through age‐prevalence patterns and two theoretical models. In 1350 subjects, the age‐prevalence of raised blood pressure, abnormal electrocardiograms, hypertriglyceridemia, hypercholesterolemia, and 2‐hour hyperglycemia, as indicators of cardiovascular disease, were studied in relation to decreases in hearing and vision, as indicators of sensory neural impairment. The age‐dependent changes in special‐sense function occurred independently of cardiovascular abnormalities. Thus a way is indicated whereby a pathologic state may be distinguished from the aging process.

Postural stability, falls and fractures in the elderly: Results from the Dubbo Osteoporosis Epidemiology Study

OBJECTIVE To assess measures of postural stability in a large population of persons aged over 60 years in order to compare performance between fallers and non-fallers and relate postural stability to fracture prevalence. METHODS The sensorimotor, visual and balance functions were measured in 1762 ambulatory, community-dwelling patients aged between 60 and 100 years (mean age, 70.1 years) living in a large semi-urban Australian city. A history of recent falls and fractures was recorded at the time of assessment. RESULTS The prevalence of impairment in all tests increased with age. Men performed significantly better than women in tests of muscle strength, visual field dependence, sway on the floor with eyes open and dynamic balance. In the 12 months before testing, 72.3% of the patients experienced no falls, 18.4% fell only once and 9.3% fell on two or more occasions. Multiple fallers had weaker quadriceps, poorer tactile sensitivity, greater visual field dependence and greater body sway than other patients. Test scores for once-only fallers were mostly between those for non-fallers and multiple fallers. Those who suffered recent fall-related fractures had significantly reduced tactile sensitivity and quadriceps strength and increased body sway. Postural stability was also impaired in patients taking psychoactive and/or anti-hypertensive medications. CONCLUSION Tests of postural stability can identify, independently of age, individuals living in the community who are at risk of falls and fall-related fractures.

Aging and the relativity of time.

ABSTRACT: The perception of passing time is related to life experience. A model for this process, similar to the relationship between stimulation and sensation in the field of physiology, is presented. It is suggested that many of the maladaptive phenomena of aging could be explained by a change in time perception with age.

An assessment of aging based on screening data.

ABSTRACT: A method for quantitating biologic age is described. Biologic age was calculated by this method from 7 different measurements made in subjects who were objectively and subjectively well. The 29 “well” subjects were selected by a computer program on the basis of the medical questionnaire, chest roentgenogram, urinalysis and electrocardiogram, from 705 “apparently well” females who attended a mutiple screening centre. These subjects had a lower calculated biologic age compared with the reference population. The model could be of value in assessing the aging rate and comparing the effect of social and environmental factors on aging in different population groups.

PRICING AND TAX OPTIONS TO REDUCE ALCOHOL‐RELATED HARMS

The report of British Columbia’s natural experiment of minimum pricing and alcohol consumption comes at a propitious time for international policy makers. It will help them to weigh up competing alcohol pricing policies between volumetric taxation and a floor price. The study showed that both beverage-specific consumption and overall alcohol consumption were reduced—a 10% increase in the minimum price on a standard drink reduced aggregate alcohol consumption by 3.4%. The authors believe that this could be a conservative estimate of the effect. For the minimum price argument to be more persuasive, the authors propose further studies on health outcomes such as hospital admissions and deaths [1]. Achieving a tax on alcohol that makes public health sense is demonstrably difficult. It is opposed by an industry capable of influencing governments and undermining alcohol policies and it is a concept difficult to explain to the general public. There are also difficulties from a public health perspective. Advocates are unclear about what they mean by a volumetric tax—is it a linear function applied to all beverages, or is it to be a tiered function applied to groups of beverages within comparable ranges of alcohol content? A minimum price has the advantage of being a simple concept, and there is now evidence from British Columbia that it will work. A meta-analysis of 112 studies of tax and price on drinking reported that a 10% increase in price was associated with a 5% decline in overall alcohol consumption [2]. As with the minimum pricing approach, to persuade a sceptical public and polity about the rationale for a volumetric tax or, indeed, a floor price, tangible outcomes will need to be modelled. What level and mix of taxes will impact on deaths, emergency department attendances, road accidents, violence, family and child harms—and a most critical question is what will happen to heavy drinkers? Taxation provides a revenue stream for government which can be hypothecated for prevention and treatment programmes. This happened from 1992 to 1997 in the Northern Territory of Australia, when that government enacted the ‘Living with Alcohol’ policy. Increased resources became available to deal with the immense alcohol-related problems among Aboriginal peoples [3]. Conversely, the minimum price approach raises revenue which would go to alcohol producers and retailers [4]. To counter these consequences, the Social Responsibility Levy on licence holders was introduced in Scotland in 2010 [5]. Projecting the consequences of alcohol pricing on outcomes in public health and social welfare becomes confounded by the countervailing responses of alcohol producers and retailers, who will act to protect their ‘bottom-lines’, and also by the growth of black market alcohol. Nor is it possible to predict the future social and economic environments in which price levers will be applied, such as changing alcohol affordability and prices, as has happened recently in Scotland [6]. This means that in implementing alcohol pricing policies there must be continuous monitoring and evaluation. From the recent Australian experience, there are some lessons for other countries planning to implement alcohol pricing policies. During a visit to Central Australian Aboriginal communities in July 2011 the Australian Minister for Health referred the public interest case for a minimum price on alcohol to the new National Preventive Health Agency for advice [7]. This came as a surprise to the public health community, as to this point the major push for a price lever on alcohol was for volumetric tax; at most, minimum pricing was seen as a subsidiary strategy. The National Alliance for Action on Alcohol (NAAA), representing more than 50 Australian health groups, has argued for a volumetric tax on alcohol as the principal strategy to reduce alcohol harms [8]. The National Preventative Health Taskforce (NPHT), commissioned to advise on excessive alcohol consumption, recommended a ‘tiered’ volumetric tax [9]. Both the NAAA and NPHT argued for hypothecation and saw minimum pricing as a complementary tactic. A step to use volumetric taxation as a public health measure was taken in April 2008, when the government imposed a tax on spirit-based ready-to-drink beverages (RTDs) in line with full-strength bottled spirits and later, in 2009, to deal with the industry’s countermeasures, a similar tax was imposed on wine and beer-based RTDs. Against the warnings of the futility of these measures, consumption of RTDs fell in the medium term with some substitution in beer and spirit sales, but not so as to lessen the reduction in overall alcohol consumption [10,11]. In parallel with these events a major review of the whole Australian tax system was in progress, and it recommended the introduction of a volumetric tax on alcohol [12]. The government rejected the recommendation and failed to include alcohol taxation in the follow-up national Tax Forum, despite active lobbying by NAAA and other organizations. bs_bs_banner